Safety-catch for elevators.



J. TARRO.

SAFETY CATCH FOR ELEVATORS.

APPLIOATION FILED JULY 29,1912. 1,064,027, Patented June 10, 1913.

LOLUMBIA PLANOOHAPH (30.. WASHINGTON, D. c.

UNITED TATE PATENT WFFICE.

JAMES 'IARRO, OF CHERRY, ILLINOIS, ASSIGNOR 0F ONE-HALF T0 WALTER\VAITE, OF CHERRY, ILLINOIS.

SAFETY-CATCH FOR ELEVATORS.

nearest.

Specification of Letters Patent.

llatented June .10, 19.13.

Application filed July 29, 1912. Serial No. 712,145.

1/ 0 all whom it may concern.

l e it known that I, Janus Tanno, a citi zen ot the United Statesresiding at Cherry, .in the county of Bureau and State of Illinois, haveinvented certain new and useful Improvements in Safetylatches forElevators; and I do declare the following to be a full, clear, and exactdescription of the in vention, such as will enable others skilled in theart to which it appertains to make and use the same.

This invention relates to improvements in safety catches for elevators.

One object of the invention is to provide a catch of this characterhaving an improved construction and arrangement ot gripping devices forfirmly gripping the guide rails of the elevator and means whereby saiddevices will be automatically and instantly operated should the hoistingcable of the elevator break.

Another object is to provide a safety device for elevators which will besimple, strong, durable and inexpensive in construction, e'tlicient andreliable in operation and which may be readily applied to elevators nowin use.

With these and other objects in View, the invention consists of certainnovel features of construction, combination and arrangement of parts aswill be more fully described and claimed.

in the accompanying drawings; Figure 1 is a vertical section through aportion of an elevatorshat't showing a side view of the upper portion ofthe elevator cage with my invention applied thereto; Fig. 2 is ahorizontal section through the elevator shaft showing a top plan of theelevator cage and the safety catches; Fig. 3 is an enlarged detail sideview of a portion of the elevator cage and one of thc catchesillustrating in full and dotted lines the operative and inoperativeposition of these parts; Fig. 4t is a detail transverse section of therail gripping member and parts cooperating therewith.

Referring more particularly to the drawings, 1 denotes the upper portionof an clevator cage which may be of any style or design and 2 denotes aportion of the framework of the shaft in which the elevator is mounted.On the opposite sides of the shaft frame 2 are secured vertical guidetracks 8 upon which the cage 1 travels. Connected to the upper cornersor top of the cage are hoisting chains lthe upper ends of which areconnected to a coupling plate 5 to which is also connected the lower endof a hoisting cable (3 as shown.

luiosely conneded to the top ot the cage adjacent to its opposite sidesand on opposite sides of the guide tracks 3 are my improved safetycatches each of which com prise a track gripping block 7 said blockshaving in their outer sides recluingular notches S the vertical sidewalls S) of which are slightly curved or convex as clearly shown in Fig.3 of. the drawings. The blocks T are 't'ormed on or suitably secured tothe inner ends of bars or plates '10 having in their outer ends shortlongitudinal slots 11 with which are connected pivot bolts 12 arrangedin the upper ends of two of the vertical bars or standards 13 formingpart of the frame of the elevator cage. The gripping devices when thusconnected to the cage have a pivotal and sliding movement which willpermit the notched ends of the blocks 7 to shift or move to a limitedextent on the tracks whereby said notched ends oi? the grips-are lockedinto engagement with and released from the guide tracks.

In order to hold the locking members in an inoperative position and topermit the same to be automatically brought to operative position at theproper time, I provide rock sha'lts 1 l which a re loosely mounted insuitable hearings on the top of the elevator cage and which have ontheir inner ends mltwardly and upwardly extending crank arms 15 whichare connected at their outer ends by chains 113 to the coupling plate 5of the hoisting chains i. ()n the outer ends of the rock shafts 1-1: areoutwardly projecting crank arms 17 the outer ends of which are providedwith laterally extending loops 18 which are slidably engaged with theplates or bars 10 of the gripping members. The crank arms 17 on theouter ends 01 the shafts l t project in an opposite direction from eachother and from the crank arms 15 on the inner ends 01' the shatts andsaid inner and outer crank arms are arranged at difl'erent angles asshown. Secured to the top oi the elevator cage 1 below the outer ends ofthe crank arms 17 and in contact therewith are llat springs 19 thepressure of which is exerted to swing the crank arms 17 and the grippingmembers 7 to which they are attached upwardly to the dotted lineposition shown in Fig. 3 wherein the side walls of the notch in saidmember will be brought into gripping engagement with the sides of theguide tracks, thereby securely holding the elevator cage againstdownward movement.

The gripping members are normally held in inoperative positions againstthe pressure of the springs 19 by the chains 16 which are connected tothe crank arms 15 on the inner ends of the rock shafts 14 and to thecoupling plate 5 of the hoisting cable 6 and chains 4., as long as saidhoisting cable 6 and chains 4 are intact. As soon, however, as the cable6 or chains 4 break and thus release or slacken the operating chains 16the springs 19 will become eifeotive and will immediately force thegripping members upwardly in position to bring the curved sides of thenotches 8 in the gripping blocks 7 into tight frictional engagement withthe guide tracks 3 which are securely wedged between the walls 9 of thenotches 8 by the cam action of said walls due to the inclined positionof the gripping blocks and members. The gripping members when thusactuated will positively hold the elevator cage at any position in theshaft where the cage may be and said members are brought instantly intooperation by the breaking or releasing of the hoisting cable 6 or thehoisting chains 4. As soon, however, as the cable or chains are repairedand weight is again placed in the elevator cage the chains 16 throughtheir connection with the hoisting cable will immediately pull upwardlyon the inner crank arms 15 of the rock shafts 14 thereby actuating theshafts 14 in the proper direction or swinging the outer ends thereofdownwardly thereby bringing the gripping members downwardly and into theposition shown in Figs. 1 and 3 of the drawings wherein the curved walls9 of the notches 8 of the gripping blocks are disengaged from the guidetracks.

The operation of my improved safety catch is automatic and positive andthe parts will become effective the moment the hoisting cable or chainsbreak thus making the elevator absolutely safe at all times and underall conditions.

From the foregoing description taken in connection with the accompanyingdrawings, the construction and operation of the invention will bereadily understood without requiring a more extended explanation.

Various changes in the form, proportion and the minor details ofconstruction may be resorted to without departing from the principle orsacrificing any of the advantages of this invention as defined andclaimed.

Having thus described my invention, what I claim, is

1. A safety catch for elevators comprising a sliding and pivotallymounted rail gripping member, a hoisting cable, a releasing shaftmounted on the cage of the elevator, a crank arm on one end of saidshaft, a loop forming the end of said arm and having an operativeconnection with said gripping member, means to connect the opposite endof said shaft with the hoisting cable of the elevator cage, whereby theshaft is rocked and the gripping member thereby held out of lockingengagement with the guide track of the elevator, and means to elevateand operatively engage said gripping member with the guide track whenthe hoisting mechanism of the elevator cage is broken.

2. In an elevator having a shaft provided with vertically-disposed guidetracks, a cage adapted to travel on said tracks, safety catchescomprising track gripping blocks having in one side track engagingnotches, adapted to engage the opposite edges of the tracks, blockattaching bars connected with said gripping blocks and having a pivotalsliding connection with a portion of the elevator cage, rock shaftsoperatively mounted on the cage and having on their outer ends crankarms, loops forming the ends of the latter, operatively connected to andembracing the attaching bars of the gripping blocks, crank arms on theinner ends of said shafts, a hoisting cable, chains to connect saidcrank arms with the hoisting cable or" the elevator, whereby while thecable is intact, the rock shafts and crank arms will be actuated to holdsaid gripping blocks in an inoperative position, and springs engagedwith the outer crank arms whereby the shafts and said blocks areactuated to grip the tracks of the elevator should said hoisting cablebecome broken.

In testimony whereof I have hereunto set my hand in presence of twosubscribing witnesses.

JAMES TARRO.

Witnesses CHAs. L. CoNNoLLY, MARY CoNNoLLY.

Copies of this patent may be obtained for five cents each, byaddressing; the Commissioner of Patents,

Washington, D. C.

